This is an open-label, non-randomized, dose finding, multiple dose Phase I/II trial of 9 aminacamptothecin (9-AC) in patients with solid tumors. The primary objective of the phase I portion is to confirm the MTD using a daily X5 schedule, and recommended dose of (-AC for the phase II portion of the study. Secondary objective of the phase I study is to determine safety profile, and to investigate pharmacodynamics parameters. The primary objective of the phase II portion is to evaluate the safety and clinical activity of 9-AC inpatients with advanced solid tumors (NSCLC, colorectal, pancreatic, gastric, bladder, prostate, head-neck and renal cell). Dose limiting toxicity was neutropenia, and the MTD was 1.8 mg/m2. Minimal clinical activity was observed, despite adequate PK parameters.